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Stable Isotope Ratio Analysis for Authenticity Control
2017This chapter summarizes terms, definitions, and reference materials used for stable isotope ratio analysis (SIRA ) of the bioelements hydrogen, carbon, and oxygen. The principles of biotic and abiotic fractionation in biomolecules like flavor compounds are explained. A short review of the common methods for the determination of isotope ratios \(\mathrm{
Norbert Christoph +3 more
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Stable lead isotope ratios in Alaskan arctic aerosols
Atmospheric Environment. Part A. General Topics, 1993Abstract Aerosol samples collected at Barrow, Alaska, during February and March 1990 were found to have uniform stable lead isotope compositions. The mean 208 Pb/ 207 Pb ratio was 2.423±0.009 and the mean 206 Pb/ 207 Pb ratio was 1.161±0.014. The latter ratio is essentially the same as that obtained from an earlier study of aerosols at two Canadian
W.T Sturges +3 more
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Silver stable isotopic ratios determined in contaminated soils
2023Silver isotopic fractionation(s) during metallurgical processes (or other high-T processes) and its fate in mining- and smelter-affected environments, Ag-contaminated soils/sediments remain entirely unknown. Regarding the Ag-ore processing (roasting/smelting technologies), it can be assumed that, similarly to other isotopic systems (e.g., Tl and Cu ...
Ales Vaněk +3 more
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High-precision measurement of chlorine stable isotope ratios
Geochimica et Cosmochimica Acta, 1993We present an analysis procedure that allows stable isotopes of chlorine to be analyzed with precision sufficient for geological and hydrological studies. The total analytical precision is ≤±0.09%., and the present known range of chloride in the surface and near-surface environment is 3.5‰.
Austin Long +5 more
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Variations of Stable Isotope Ratios in Nature
1973Information about nonterrestrial isotopic abundances can be obtained from studies of meteoritic, lunar, or planetary dust materials from both space probes and from ground-based astronomical observations. From these different sources of information it has been established that many elements have cosmic isotopic compositions which are very different from
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Stable Carbon Isotope Ratios as Water Quality Indicators
1975Stable carbon isotope ratios (C13/C12) of man-made organic substances such as petrochemicals and pulp mill effluents are generally different from those of the “natural” organic matter in marine environments. By measuring the C13/C12 ratios of background organic matter in the marine environment and the pollution sources, an estimate of the degree of man-
FC Tan, GJ Pearson
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DETERMINATION OF STABLE ISOTOPE RATIOS IN FOOD ANALYSIS
Food Reviews International, 2001Within the last few years, stable isotope analysis has gained increasing importance in authenticity control of food and food ingredients. The development of the methodology from its start in the geological sciences is reviewed, the requirements and the specific features of the technique in the area of food quality assessment are outlined, and the ...
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Stable Isotope Ratios as a Biomarker on Mars
Space Science Reviews, 2007As both Earth and Mars have had similar environmental conditions at least for some extended time early in their history (Jakosky and Phillips in Nature 412:237–244, 2001), the intriguing question arises whether life originated and evolved on Mars as it did on Earth (McKay and Stoker in Rev. Geophys. 27:189–214, 1989).
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Stable isotope ratio measurement using a laser microprobe
1995Many elements have two or more stable isotopes and can, therefore, be usefully studied for variations in their isotope ratios. These isotopes, unlike those of the radioactive variety, are completely stable and do not disintegrate with time. As such, when a non-volatile material such as a mineral is formed, the constituent elements should theoretically ...
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Stable carbon isotope ratios in orange juice
Journal of Agricultural and Food Chemistry, 1981Landis W. Doner, Donald D. Bills
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